Heretofore, as an example of the imaging device of this type, there has been known the technique disclosed in PTL 1. PTL 1 discloses an imaging device including a substrate, an imaging unit, and left and right paired light emitting diode (LED) elements. The substrate has a surface on which wiring is formed. The imaging unit is mounted on the surface of the substrate at a location that is a center of the surface of the substrate when viewed in a left-right direction, and the imaging unit is electrically connected to the substrate. The LED elements are mounted on the surface of the substrate such that the LED elements are arranged on left and right sides of the imaging unit and are away from the imaging unit by a certain distance. The LED elements are electrically connected to the substrate.
PTL 2 discloses a head-up display device configured to project a display image onto a windshield of a vehicle. The head-up display device includes a substrate having a surface on which wiring is formed, a pair of LED elements mounted on the surface of the substrate and electrically connected to the substrate, and a heatsink having a front surface being in contact with and fixed to a back surface of the substrate. The heatsink is provided for the purpose of dissipating heat of the substrate. The heatsink includes a base portion whose front surface has a flat shape and fins integrally protruding from a rear surface of the base portion and being spaced from each other.